饲粮维生素D添加水平对蛋雏鸭免疫及抗氧化功能的影响

Effects of Dietary Vitamin D Level on Immune and Antioxidant Functions of Egg-Type Ducklings

本试验旨在研究饲粮维生素D添加水平对1～28日龄蛋雏鸭免疫及抗氧化功能的影响,以探讨饲粮维生素D的适宜添加量。试验选取健康、体重相近的1日龄金定蛋雏鸭180只,随机分为5组(Ⅰ～Ⅴ组),每组6个重复,每个重复6只试鸭。采用玉米-豆粕型基础饲粮,Ⅰ组(对照组)试鸭饲喂基础饲粮,Ⅱ～Ⅴ组试鸭分别饲喂在基础饲粮中添加110、220、550、1 000 IU/kg维生素D的试验饲粮,试验期4周。结果表明:饲粮添加550 IU/kg维生素D可显著提高胸腺指数、脾脏指数(P<0.05),并显著增强肝脏超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05),降低血清白细胞介素-2(IL-2)及血清和肝脏丙二醛(MDA)含量(P<0.05);饲粮添加220、550 IU/kg维生素D可显著提高血清总蛋白(TP)和白蛋白(ALB)含量(P<0.05),并显著增强血清SOD和GSH-Px活性及血清和肝脏总抗氧化能力(T-AOC)(P<0.05)。综合本试验结果,在玉米-豆粕型基础饲粮中添加适量的维生素D可提高1～28日龄蛋雏鸭的免疫及抗氧化功能。综合考虑各指标,通过二次回归模型估测得出维生素D适宜添加量为512.8～550.0 IU/kg。

This experiment was conducted to investigate the effects of dietary vitamin D level on immune and antioxidant functions of egg-type ducklings aged 1 to 28 days,and to estimate the optimal dietary vitamin D level.A total of 180 one-day-old healthy Jinding egg-type ducklings with the similar body weight were randomly assigned to 5 groups with 6 replicates per group and 6 ducklings per replicate.The ducklings in the group Ⅰ(control group) were fed a basal diet(corn-soybean meal-based diet),and those in groups Ⅱ to Ⅴ were fed the basal diet supplemented with 110,220,550 and 1 000 IU/kg vitamin D,respectively.The experiment lasted for 4 weeks.The results showed as follows: supplementation of 550 IU/kg vitamin D significantly increased the thymus and spleen indices(P<0.05),and improved the activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) in liver(P<0.05),while reduced the contents of interleukin-2(IL-2) in serum and malondialdehyde(MDA) in serum and liver(P<0.05).Supplementation of 220 and 550 IU/kg vitamin D both significantly increased the contents of total protein(TP) and albumin(ALB) in serum(P<0.05),and improved the activities of SOD and GSH-Px in serum(P<0.05) and total anti-oxidant capability(T-AOC) in serum and liver(P<0.05).These results indicate that corn-soybean meal-based diet supplemented with moderate level of vitamin D can increase the egg-type ducklings immune and antioxidant functions.Based on the various indicators,the optimal vitamin D supplemental levels estimated by quadratic regression model analysis are 512.8 to 550.0 IU/kg.